1. Field of the Invention
The invention relates to an electrical connector, and more particularly to a male electrical connector with a socket shell.
2. Related Art
At present, the most popular signal transmission specification for the computer apparatus is the universal serial bus (USB). A female connector socket and a transmission cable manufactured according to this specification can be immediately used to connect a peripheral apparatus, such as a mouse, a keyboard or the like, to the computer in a plug-and-play manner.
At present, the USB specifications contain USB 2.0 and USB 3.0 specifications. As shown in FIG. 1, an existing USB 2.0 male connector or plug 90 includes a plastic seat 91 and a metal casing 92 covering the plastic seat 91. A socket space 93 is formed between the metal casing 92 and the plastic seat 91. Only one surface of the plastic seat 91 is provided with one row of connection contacts 94 exposed to the socket space 93. At present, the official specifications of the USB association include the overall height “i” equal to 4.5 mm, the half height “j” of the socket space 93 equal to 2.25 mm, and the height “k” of the socket space equal to 1.95 mm. At present, the USB 2.0 female socket has an inner tongue having one surface provided with one row of connection contacts. In use, the USB 2.0 plug needs to be inserted in a correct direction to align the connection contacts of the plug and the socket with each other for electrical connection. In order to ensure the electrical connection upon the insertion of the USB plug, both the socket and the plug have the mistake-proof designs. As shown in FIG. 1A, when a mark 97 on one surface of a handle 96 connected to the USB 2.0 male connector 90 faces upwards, the connector 90 is in a forward state. At this time, the connection contacts 94 face upwards. When the male connector 90 is forwardly inserted, the electrical connection can be established, as shown in FIG. 1B. However, the USB plug cannot be reversely inserted so that the electrical connection cannot be established. The user usually randomly inserts the USB plug, so the possibility of insertion failure is equal to ½. So, the user often has to insert the plug twice in an inconvenient manner.
Referring to FIG. 2, an existing USB 2.0 female socket 80 includes a plastic seat 81, a metal casing 83 and one row of terminals 87. The front end of the plastic seat 81 is integrally formed with a horizontally extended tongue 82. The metal casing 83 is positioned at the front end of the plastic seat 81 to form a connection slot 84. The tongue 82 is disposed near the lower section of the connection slot 84. The one row of terminals 87 include four terminals fixed to the plastic seat 81 and extending frontward and arranged on the tongue 82, and a projecting connection contact 88 is formed near the distal end of the terminal 87.
The USB 2.0 female socket 80 has to provide the mistake-proof design in conjunction with the male connector, and the official specifications of the USB association are as follows: the height “o” of the connection slot is equal to 5.12 mm, the thickness “p” of the tongue is equal to 1.84 mm, the height “s” above the tongue is equal to 0.72 mm, and the height “q” below the tongue is equal to 2.56 mm. Thus, the USB 2.0 male connector 90 needs to be inserted with the connection contact 94 facing downwards, so that the socket space 93 and the tongue 82 can be fitted and positioned with each other, wherein the half height “j” (2.25 mm) is inserted into the height “q” (2.56 mm) below the tongue. If the USB 2.0 male connector 90 is reversed, it cannot be inserted.
As shown in FIG. 2A, an existing USB 3.0 female socket 85 has the associated dimensions and structure substantially the same as those of the USB 2.0 female socket 80 except for the difference that the tongue 82 of the USB 3.0 female socket 85 is longer and the front section of the USB 3.0 female socket 85 is provided with five second connection contacts 89 that cannot be moved elastically.
The USB 3.0 male connector has the structure and the associated dimensions substantially the same as those of the USB 2.0 male connector 90 except for the difference that the USB 3.0 additionally has one row of five connection contacts, which project from the socket space and can be moved elastically.
In either the conventional USB 2.0 or USB 3.0 female socket, only the simplex contact pattern is provided. In use, the male connector cannot be bidirectionally inserted into the female socket for electrical connection. For the sake of the convenience in use, it is preferred that the male connector can be bidirectionally inserted into the female socket for electrical connection.